I wasn’t born with a good ear and into a musical family that supported me. I didn’t get piano lessons, and was actively discouraged and steered away from any traditional forms of learning such as Marching Band or Chorus in school. When I started pursuit of guitar as a teenager on a crappy inst that I bought with my own money working odd jobs I had basically 2 ways to learn. There was no money for lessons and I wouldn’t have known how to seek a teacher if there was.
1)Watch a buddy do it and mimic them, or 2) learn the odd tab from Guitar Player. I really never learned to tune the darn thing until I saved up for one of the first digital electronic tuners, and it was super expensive for the time, I think it cost me $65 in 1975 or 76. Once I could get the darn thing in tune the same way every time on my own, then I had a prayer of actually developing my ear. I found a good little book that taught the maj and minor pent patterns and that helped me get a foothold towards improvising and learning the neck. I learned to fake a simple solo, but figuring out stuff by ear was still an impossible task.
I had a hard time distinguishing the fundamental from the overtones, I tended to hear the whole sound all at once and it was confusing. I really didn’t realize this was the problem at the time but sometime around my 2nd yr in college I stumbled upon a way forward out of a stubborn refusal to not give up.
I gave up on the rock/prog/fusion fantasy and scrimped and saved and bought a decent playable Alvarez acoustic for around $200. Bought a couple of songbooks full of 3 chord folk, bluegrass, Gospel, and country tunes that I’d heard all my life and started learning to sing and play those. I jammed around campfires and living rooms playing that stuff, eventually graduating to bluegrass bands, always trying to work my way into situations with better players for at least a 10 year period. If it got me in the door, I’d gladly play bass. Thru sheer repetition I learned how to hear I,IV, V and the major scale. This put me in a place most people get to when they are a teenager, but I was into my 30s by that point.
Thru all this time I studied all kinds of stuff, but it took me years of sticking to the basics before a lot of could take root.
I’m an old man now, but still on the journey.